The best way to learn mathematics is to do mathematics.
"A great book is one that leaves you changed, with a new perspective on life and a deeper understanding of the human condition."
Mathematics is not a deductive science—that's a cliché. When you try to prove a theorem, you don't just list the hypotheses and then start to reason. What you do is trial and error, experimentation, guesswork.
The future belongs to those who are willing to adapt and learn.